A flaw was found in the way the FtpClient implementation in the Networking component of OpenJDK handled responses to the FTP PASV command. A malicious FTP server could cause a Java application using FtpClient to connect to a host and port that is not accessible from the FTP server and perform port scanning or banner extraction.

The fix for this issue prevents FtpClient from connecting to hosts different form the server used for the main FTP connection. As this fix may break certain FTP deployments, a newly introduced system property jdk.net.ftp.trustPasvAddress can be used to make FtpClient connect to any host specified in the PASV command response.

A flaw was found in the way the Library component of OpenJDK handled JAR files containing multiple MANIFEST.MF files. Such JAR files could cause signature verification process to return an incorrect result, possibly allowing tampering with signed JAR files. After the fix, all JAR files with multiple MANIFEST.MF files are treated as unsigned.

In musl libc through 1.2.1, wcsnrtombs mishandles particular combinations of destination buffer size and source character limit, as demonstrated by an invalid write access (buffer overflow).